Cartilage is a highly specialized tissue which functions to resist compression and to absorb shock. The purpose of this project is to understand molecular mechanisms by which genes for cartilage components are regulated and expressed during normal development and in disease states. The alteration of cartilage matrix protein are likely to be associated with human diseases such as osteoporosis, osteoarthritis, and rheumatoid arthritis. We have determined the primary structure of some of the cartilage components. We have also isolated and characterized genes for these proteins. DNA elements which regulate these genes have been identified and nuclear protein factors bound to them have been characterized. Structure and function relationship has been studied using expression vectors and synthetic peptide approaches. DNA prepared from patients with chondrodysplasia has been screened to examine their linkage to cartilage genes.